Engine trunk-piston.



M. G, CHANDLER. ENGINE TRUNK PISTON.

APPLICATION FILED Ammo, 1914.

1,114,229. i 1 Patented oct.2o,1914.

'elevation through .latter With CHANDLER, GF HCAG, ILLNOS.

ML'EORD G.

*nr "in "n nevermind li li'ilhNT e EN'G'NE TRUNY-PSTN.

Application tiled April 3G, 19M.

To all whom, it 'ma 1/ concern Be it known that l, Minronn Gr. CHANDLER,a citizen of the United States, residingl at Chicago, in the county ofCook and State of Illinois, have invented a. new and useful Improvementin Engine Trunlelistons, of which tliefollowing is a speciication. l

it is a matter of great importance, especially in high-speed internalcombustion engines, that the trunk-pistons be as light in Weight aspossible, consistentwith the requisite strength and freedom iiropidistortion on the power-stroken The bearings in the pistons 'for therods connecting the piston-rods to the pistons are required to berelatively long, as'compared with the thickness of the pistonvvall, andtherefore it is common practice to provide opposed bosses on the pistonsin which the pins are journaled. is pistons have hitherto beenconstructed when oli relatively light-Weight construction, the leverageexerted on the power-stroke bythe pin, intermediate its ends, on theWall of the piston above the bosses, causes that portion of the pistonabove the bosses, which bears against the cylinder, to be distorted andbear with such'pressure against the cylinder that swig/lingl o thecylinder often results. shallybe as light, 'i not lighter, in Weightthan those hitherto constructed, and in which iiexing, oi' springing, ofthe 4pin-bosses will be reduced to the minimum, and in case springingdoes occur, the'bearing surfaces of the piston will not be distorted,and thus scoring ci the cylinder will be avoided, A further object is toprovide a piston of such construction that its inner surface may bereadily machined.

Referringto the accompanying drawing, wherein my" 'mproved iston isshown as `used in an internal com nstidn engine, the View therein shownis in vertical sectional i the cylinder and piston, the piston-rod andpin for connecting; the the piston being shown in elevas tion.

In carrying out my directly above the bosses 2 for the pm which connectsthegpiston with the piston 'rod 4, is annularly recessed` on the outeriston, as indicated at 5; to render this Wal relatively thin, inpractice.Y where 'al piston of three and one-fourth inches in diameteris used, this wall beingsurface of the object is to rovide a pistonwhich Specincaton of )Letters Eaten Patented fillet. 2d, Mil, serial no.essi-sae.

inch thick, whereby this Wall, when the pis ron is constructed from themetal usually dered inherently springy to a slight degree.

lower end of the wall l the pin 3, and thus joins with these bearingsintermediate the ends of, and wholly above, the latter, as represented,thereby preserv ing full length bearings for the pin 3. Furthermore, byinsetting the Wall@ to the outer ends of the, bearings, ance adorded bythe wall of the piston above the bearings, to the iiexing, of thebearings under the, povvenstroke, 1s greatly augmented, as compared Witha structure wherein the Wall of the piston, above the bearings, connectstherewith atthe outer ends of the latter.

The recess 5 terminates at its upper preferably at of the piston adaptedto slidingly engage the inner surface of the cylinder, represented at 7,this recess preferably extending up into the resisting-portion 6,whereby, desirable Width of the bearing surface, serves to aid inreducing the weight of the piston. Above the bearing-surface ,6, one ormore piston-ring-receiving grooves 8 are provided for receivingpiston-rings 9, two or such grooves being shown in the constructionillustrated. The piston is preiera ly of slightly reduced diameterbetween the face l0 ingsurface located below the bearings for the pin 3and preferably at the lower end of the piston.

-The provision of the relatively thin and springy Wall l, above thebearings for the pin 3., is a very desirable feature oi my iniprovedpiston, as the piston may be made relatively light at this portion ofthe latter,

invention, the Wall 1,',-

and should the resistance afforded by the or" Which the' piston is apart, to the movement of the piston, be suliiciently great to cause thebearings for the pin 3 to spring on portion 6 of the piston will notdistort, but

will maintain its 'true circular form, pre` ventingscoring ot thecylinder. Thus by providing a piston with either ot the 'feaprefrablyabout three thirty-seconds of an '1 tures above stated, namely that ofinsetting l, relativev or springing, n

l side an annular bearing-portion 6 piston-rod Il, in the operation ofthe engine A employed in. piston-constructions, is ren- 'I By rccessingthe piston, as described, the is inset relative to the ,entire outerends of the bearings for -Y the portion of the piston forming the bear-,

while preserving a' es l' bear."- Gand an annular bearing-surthepower-stroke, thewall 1, by reason of its v springiness, will distort,but the bearinglee weil innnediziey above the bearings for he pin 3, andDres-erung full length bearl ing foi' i:he latter, and form-ing thisWil-i1 i'elntiveiy thin land of springy metal, and G51.'

What I claim as new and desire to secure Aby Letters Patent is- Athink-piston with iiemetricaHy-opposed bosses forming bearings for theps' ton-Tori pin, the Wall of the pist-on above said bosses andconnected with the latterbeng single and integral with the closed end ofthe piston, packing-ring grooves in said wall, the 'portion of said wellbetween the lowerinost of said grooves and said bosses being insetrelative to the outer ends of said bosses and the groove-equippedportion of sind wall and relatively thin. und springy, with the outerends of said bearings extending throughout their cireumferences Whollybeyond said insetl portion of the Wall, and the 'outer ends of saidbosses merging into the circular piston Wall.

MILFORD G. CHANDLER. In presence of- D. (Y THORSEN, O. C. AvIsUs.

